Suspended railway.



R. PETERSEN. SUSPENDED RAILWAY. APPLICATION FILED NOVA), 1908.

Patented Oct. 5, 1909.

CID

mzmzw. a. mwlm co. PNDTO-LITNOGRAPNERS. wnseummu, n. cy

RICHARD PETERSEN, F BERLIN, GERMANY.

SUSPENDED RAILNAY.

Specification of Letters Patent.

Patented Got. 5, 1999.

Application filed November 9, 1908. Serial No. 461,680.

To all whom it may concern:

Be it known that I, RICHARD PETERSEN, a subject of the German Emperor,and residing at Berlin, Germany, have invented certain new and usefulImprovements in Suspended Railways, of which the following is aspecification.

My invention relates to elevated railways of the known kind in whichtramway, supported by a series of single columns, has its frame for therails supported upon the capitals of the columns, and a primary objectis to provide an elevated railway viaduct having a flat, horizontalgirder forming the tramway which is so stiff that not only is a firm andsafe support occupying but comparatively small space provided, but whichis also so rigid that it does not bend appreciably horizontally owing tothe forces acting upon it. due to one-sided loads and to the oscillatorymotions of the vehicle suspended therefrom.

For a suspended car to travel more smoothly than a surface railway-caritis as necessary to provide a much more exact track, since, inconsequence of the possibility of the car swinging out freely laterally,the irregularities in the track cause oscillatory motions of the vehiclein so far as such irregularities are sudden alterations in the radius ofcurvature of the track.

The difficulty of constructing a suspended railway viaduct havingcentral supports was that, having re ard to the street tratlic, thecentral supports had to be kept as narrow as possible, but, on the otherhand, when the breadth of these supports limited, owing to the supportsbending in consequence of a one-sided load, the distance which the headsof the supports move laterally increases. in the calculated estimatesthis lateral bending attained an amount which was inadmissible for thesmooth running of the suspended railway. Further, when endeavoring toreplace the high lattice bridge-girders by low solid-sided or rolledgirders, it was found that these would loend too much if they wereconstructed as simple beams which are interrupted at each support, orthe height of girders would be too great for them to be able to bearranged advantageously under the rails having regard to theconstruction of the cars. Also the strains on the vertical principal.girder would be too great if they were arranged passing over severalsupports, in consequence of the vertical movability of the )OlIltS ofsupport which is connected with the head of the support yieldinglaterally. All these contradictions in the constructional conditions areavoided when, in accordance ith the invention, the heads of the supportsare coupled with one another by one broad horizontal lattice-girder insuch manner that one individual support cannot bend laterally by itself,but the adjacent supports must participate in its movement.

An exceedingly suitable construction is obtained when the principalchords of this lattice-girder are formed by the solid verticalrail-carrying girders, whereby a horizontal girder of such stiffness isformed that the horizontal deformations of the track are so fiat thatthey can no longer exercise any injurious influence on the smoothness ofthe running of the car.

In order that the invention may be clearly understood, reference will bemade to the accompanying drawing in which one constructional form ofviaduct for a suspended railway is represented by way of example, and inwhich 1- Figure 1 is a side elevation, Fig. 2 a transverse sectionalelevation in two diiferent planes, and Fig. 3 a plan, the lefthand sideof Fig. 2 being a section in the plane a7) and the right-hand side asection in the plane c(Z in Fig.

Referring to the drawing, the central supports l are provided with heads2, to which are attached the rail carriers The latter are girders ofsuitable length to which are attached the members 4. The latter togetherwith the rail carriers 3 and the heads of the central support form oneflat horizontal lattice-girder, the principal chords of which are thegirders 3, the entire lattice girder being carried by the centralsupports 1. The car 5 is suspended in known manner from the truck frames6 which run on the rail 7 carried by the girder 3.

As mentioned above, the horizontal girder comprising the heads 2 of thesupports 1, the principal chords 3, and the interconnecting members t ismade so stiff that the horizontal deformations of the rail 7 from therectilinear or from the curvature originally given to it are so slightthat the smooth running of the car is not injuriously affected. Nowowing to the reciprocal displace ment of the heads of the supportsbecoming limited to a very small amount, the advantage is simultaneouslyobtained that the reciprocal vertical displacement of the points i ofsupport of the vertical rail carriers becomes so small that these cannow be looked upon practically as continuous girders on almost rigidsupports. Accordingly it is possible to reduce the height of thesegirders to such an extent that they can be used with the customaryconstruction of car without their bending too much vertically. l

In known suspended railways which have l been built heretofore theindividual bridge- I girders are constructed as simple beams be- I tweenthe supports. In consequence of the horizontal n'iovement of thesupports in the j transverse plane of the viaduct owing to their bendingwhen they are loaded on one side, the line representing the position ofthe rails forms beside the curvilinear bend of the individualbridge-girders a polygonal line passing through the junctions of the jbridges, the points of the angles of which are situated under the loadedsupports. Correspondingly, in the constructional form of viaductaccording to the present invention the individual sections of theviaduct l between each two expansion joints forml members of a polygon,the shape of which l varies when the viaduct is loaded on one side. Theshorter the individual members are, the more injurious is the effect ofthe bending of the supports in the transverse plane. In order to makethis influence noninjurious, it is desirable to make the connectedlengths of viaduct as long as possible. The length is limited on the onehand by the necessity of providing the above mentioned expansion jointsat certain intervals, but still more by the circumstance that the narrowcentral supports cannot be arranged as a pivoted pendulum in thelongitudinal direction of the railway, because the forces which occur atthe bottom end of the shaft l of the column are much too great for apractical articulated construction to be possible. I If the supports aremade very stiff in the longitudinal direction of the viaduct, howl ever,having regard to the secondary tensions which occur, the length ofcontinuous viaduct which is present in each case could be only small.

The idea of making the central supports l in the longitudinal directionof the railway as flexible as possible and of constructing between twoexpansion joints always only one support as a fixed yoke gives, inconnection with the principal feature of the invention, a technicallyvery suitable arrangement of the railway viaduct which is distinguishedby comparatively small cost of matcrial.

hat I claim as my invention and desire to secure by Letters Patent is:

1. An iron elevated railway viaduct for suspended cars comprising incombination a plurality of sections, each section consisting of morethan two central supports each having a head, and a flat, uninterrupted,horizontal, rigid lattice-girder, substantially as shown, connectedrigidly with the heads of said supports, said sections being connectedone with another by expansion joints, as set forth.

2. An iron elevated railway viaduct for suspended cars comprising incombination a plurality of sections, each section consisting of morethan two central supports each having a head, two continuous principalchords of a lattice-girder connected with said heads, andinterconnecting members, substantially as shown connecting saidprincipal chords, said sections being joined one to another by expansionjoints, as set forth.

3. An iron elevated railway viaduct for suspended cars, comprising incombination a plurality of sections, each section consisting of morethan two central supports each having a head, and a flat, uninterrupted,horizontal, rigid lattice-girder, substantially as shown, connectedrigidly with the heads of said supports, said sections being connectedone with another by expansion joints, the moment of inertia of thecross-section of the supports with regard to the transverse plane of theviaduct being as small as is permissible having regard to security frombending, for the purpose specified.

ln testimony whereof, I afix my signature in the presence of twowitnesses.

RICHARD PETERSEN.

itnesses:

EDWARD E. HAEMMEL, J OHANNES F. H. GRUMMEL.

